新型液电混合原理高能效驱动重型机械臂的设计理论与方法

Hydraulic controlled heavy duty manipulators are widely used to lift the load in construction machinery, and the throttle control method is currently used in order to meet the operation characteristics. During the manipulators dropping, the large amount of gravity potential energy accumulated by the mechanical boom is converted into heat and dissipated by the throttling of control valve, which causes great energy waste. To reduce the temperature of hydraulic oil, additional cooling devices is necessary, which further increase the energy consumption. Because the energy conversion principle is not clear and the control method is unreasonable, this problem has not been effectively solved so far, and it is a key technical problem that restricts the efficient operation of construction machinery. Therefore, this project proposes an innovative hydraulic and electric compound solution that integrates the conversion of gravity potential energy to hydraulic energy directly by accumulator and efficient motion controlled by the electric linear drives. Based on the involved scientific issues of efficient energy conversion mechanism, performance causes, control strategies and so on, various aspects of researches are carried out, including design theory of the novel drive system, system performance cause and evolution law under single electric control and electric hydraulic compound control, multidisciplinary modeling, control strategies based on energy balance and conversion, comprehensive evaluation of typical applications, etc. By the explosion of design theories and control methods of heavy duty manipulators drive system with lower installed power, less energy conversion links, shorter transmission chain and better operation performance, the matching rules of energy transfer and operation performance are mastered. The project will provide scientific basis for the native independent research and development of energy-saving and low-carbon construction machinery.

工程装备广泛采用液压控制的重型机械臂提升负载，为满足运行特性要求，目前主要采用节流控制方式。下放过程中，机械臂集聚的大容量重力势能经控制阀转换为热量耗散掉，产生极大的能量浪费，附加的冷却装置进一步加剧了系统能耗。由于能量转换机制不明确和控制方式不合理，这一问题至今未能有效解决，成为制约工程装备高能效运行的关键技术难题。为此，本申请提出重力势能液压方式直接转换利用与电气直线驱动混合的创新方案，围绕该方案涉及的能量转换机理、性能成因与调控策略等科学问题，在新型驱动系统设计理论、电气独立调控与电气液压复合调控下系统性能成因与演变规律、多学科建模、基于能量平衡转换的控制策略、典型应用的综合评价等方面开展研究，探索装机功率小、能量转换环节少、传递链短、运行特性优良的重型机械臂驱动系统设计理论和控制方法，掌握其能量转换传递与运行特性的匹配规律，为我国自主研发节能环保、绿色低碳的工程装备提供科学依据。

针对工程装备动势能浪费及节流损失大等痛点，项目从能量转换机理出发，提出采用液压缸-蓄能器组合与电动缸共同驱动重型机械臂的液-电混合主被动驱动方法，液压缸承受机械臂重力载荷，电动缸驱动外载和惯性载荷，电气与液压两者自然解耦，充分利用重力势能液压方式直接转换能效高和电气直线驱动能效高与控制精度高的优势，实现极低能耗的机械臂高性能驱动。. 为匹配重型机械臂载荷特性，分别设计了电气独立控制液-电混合驱动系统、电气液压复合控制液-电混合驱动系统、及四象限运行液-电混合驱动系统，并重点开展了系统解耦控制、性能成因、演变规律、运动特性、能效特性和宽工况域典型应用等方面的研究，探索机械臂重力势能回收利用率最大化、运动特性最优化的系统设计方法和控制策略，掌握了机械臂高能效、高速平稳运行的设计理论、控制方法与关键技术。建立了能够对液-电混合驱动系统特性进行分析和综合评价的多学科数字样机和试验平台。研究结果表明，采用新型液-电混合驱动系统，重型机械臂重力势能回收利用效率可达70%，用于液压挖掘机，可使整机能效相对现有负载敏感系统，由不足20%提高到了50 %以上。研究成果在装载机、起重机、压力机等多种装备上同样具有广泛的应用前景，为工程装备动势能回收利用提供了新的方案，为我国研发绿色、环保、节能的工程机械装备奠定了理论基础。. 已发表（录用）学术论文20篇，其中SCI收录期刊论文4篇，EI收录期刊论文5篇，2篇国际会议论文获最佳论文奖，获授权发明专利15件，培养博士研究生3人，硕士研究生5人，获上银机械优秀博士论文奖银奖1篇、省优博士学位论文2篇。